Synthesis of Dialkyl [1-Hydroxy-2,2-dimethyl-3-(dialkylamino)propyl]phosphonates

Russian Journal of General Chemistry -     

Synthesis of 3-Amino-2,2-dimethyl-8-thia-1-azaspiro[4.5]decane

The synthesis of 3-amino-2,2-dimethyl-8-thia-1-azaspiro[4.5]decane is described. Key steps include the addition of prenyl magnesium bromide to a 4-methoxybenzylimine without reversal of stereochemistry and the iodine-initiated aminocyclization to form the azaspirocycle.     

Umsetzungen von 3-(Dimethylamino)-2,2-dimethyl-2H-azirin mit Barbitursäure-Derivaten

Reactions of 3-(Dimethylamino)-2,2-dimethyl-2H-azirines with Barbituric-Acid Derivatives The reaction of 3-(dimethylamino)-2,2-dimethyl-2H-azirine ( 1 ) and 5,5-disubstituted barbituric acids 5 in i-PrOH at ca. 70° gives 2-[5-(dimethylamino)-4,4-dimethyl-4H-imidazol-2-yl]alkanamides of type 6 in good yields (Scheme 1). The formation of 6 proceeds with loss of CO₂; various reaction mechanisms with a zwitterionic 1:1 adduct B as common intermediate are discussed (Schemes 2 and 5). Thermolysis of product 6 leads to 2-alkyl-5-(dimethylamino)-4,4-dimethyl-4H-imidazoles 8 or the tautomeric 2-alkylidene derivatives 8 ′ via elimination of HNCO (Scheme 3). The latter undergoes trimerization to give 1,3,5-triazine-2,4,6-trione. No reaction is observed with 1,5,5-trisubstituted barbiturates and 1 in refluxing i-PrOH, but an N-alkylation of the barbiturate occurs in the presence of morpholine (Scheme 4). This astonishing reaction is explained by a mechanism via formation of the 2-alkoxy-2-(dimethylamino )aziridinium ion H which undergoes ring opening to give the O-alkylated 2-amino-N¹,N¹-dimethylisobutyramide I as alkylating reagent (Scheme 4).     

Synthesis of 5-[bromo(aryl)methyl]-2,2-dimethyl-1,3-oxazolidin-4-ones

A Darzens condensation of α-chloroacetamide with aromatic aldehydes furnished a series of 3-aryl-2,3-epoxypropionamides, which were further converted to 5-[bromo(aryl)methyl]-2,2-dimethyl-1,3-oxazolidin-2-ones.     

Acyl- und Alkylidenarsane. IV [1] Molekül- und Kristallstruktur des 2,4-Di(tert. butyl)-1,3-dimethyl-2,4-bis(trimethylsiloxy)-1,3-diarsetans

Bis-Nitridochloro Complexes Cl₃PO? (Cl₄)M?N? C₂Cl₄? N?M(Cl₄)? OPCl₃ with M = Mo, W, Re By the reaction of cyanogen with tungstenhexachloride, as well as by the reactions of cyanogen and chlorine with molybdenum-, tungsten- and rheniumpentachloride, in POCl₃ solution the POCl₃ solvated bis-nitridochloro complexes Cl₃PO? (Cl₄)M?N? C₂Cl₄? N?M(Cl₄)? OPCl₃ can be obtained. The i.r. spectra indicate that the complexes contain metal nitrogen triple bonds with a linear M?N? C arrangement. The O atoms of the POCl₃ molecules are coordinated in trans-position to the M?N triple bond.